Floor construction



March 31, 1931. K. P. BILLNERA FLOOR CONSTRUCTION Filed May 19, 19:50

INVENTOR ATTORNEY III/11111111! Patented Mar. 31 1931 PATENT OFFICE KARLP. BILLNER, NEW YORK, N. Y.

FLOOR CONSTRUCTION Application filed Kay 19,

In ap lication for Letters Patent of the United tates, filed February 7,1930, Serial No. 426,519, I disclosed certain improvements in floorconstruction in which light steel '5 girders or bar joists are employed,running crosswise of the floor and embedded in and supported andreinforced by a filling of porous concrete or so-called aerocrete. Mypresent invention relates to a floor construction of the same generaltype but embodies improvements by reason of which the con struction willbe substantially stronger and more rigid for the same weight ofmaterials.

With the arrangement described in m pending application, as well as withall floor constructions in which steel girders or beams have been used,so far as I am aware, the

construction has always been what is tech nically referred to as thesingle span type. By this is meant that the strength of each span isindependent of other s ans. For this reason in making calculations basedupon assumed loads, the dimensions and sizes of the girders or beams arebased upon the load intended to be carried by each span, whollyindependent of the other spans.

With my present improvements, I employ a continuous construction throughtwo or more spans, as I will explain, whereby the girders or beams arenot independent, and in consequence a very much lighter type, of girderor beam can be employed to resist the same load. In a sense theadvantage secured in this direction is somewhat cumulative, for thereason that the dead weight of the floor is reduced whereby a saving insteel results from this fact.

In order that the invention may be better understood attention isdirected to the accompanying drawing forming a part of thisspecification and in which Figure 1 is a cross section ment of floorconstruction employing light weight girders or bar joists, and

Figure 2 is a similar view of a floor construction employing transverseI beams.

In both of these views corresponding parts are represented by the samenumerals of reference.

With the arrangement shown in Figure 1,

of an arrange- 1930. Serial No. 453,679.

I make use of a series of longitudinal I beams 1, or other form of beamcarried in the ordinary way upon posts or pillars (not shown), the beamsat the extreme ends being supported by the usual walls of the buildingas will be understood. The I beams 1 are spaced a proper distance apart,usually not to exceed a maximum of twenty-four feet and extend parallelto each other. Extending crosswise of the I beams and supported by thesame are light steel girders or bar joists which can be of any suitableconstruction,

a number of which are referred to in my said application. These are nowwell known elements in building construction, differing in detailaccording to different manufacturers or steel fabricators. Their steelcharacteristic is that they provide great strength with but small weightof steel. These girders are placed generally from twenty to twenty-fourinfihes apart and extend parallel with each 0t er.

The form of girder shown in Figure 1 is merely for the purpose ofillustration. It consists of one top flange 2, one bottom flange 3, andinterposed members 4 welded or otherwise secured between the top andbottom flanges, so that the whole forms a light latticedflgirder. Asshown, the ends of the bottom ange of each girder are bent up at anangle of ninety degrees more or less, being welded or otherwise securedto the top flange. The girders so formed rest directly upon the upperflange of the I beams 1.

In the arrangement illustrated, I show a pair of plates 5 and 6 whichare welded or otherwise secured to the members 2 and 3 and which alsorest upon the upper flanges of the I beams. Preferably these plates aresomewhat longer than the width of the upper flange of the I beam asshown, so as to strengthen the ends of the girders in such manner thatthey will be able to withstand the tension occurring at these pointsunder the effect of loads. The plate 5 of one girder, if used, or themembers 2 and 3 of that girder, if said plate is not used, are securelytied to the plate 6 of the adjacent 'rder, if used, or to the members 2and 3 0 that girder if said plate is not used. This tying of the a headsof the keys 7 not only engage recesses in the plates 5 and 6 but alsoshallower channels in the flat upper portions of the flanges 3.

By thus rigidly connecting adjacent girders together, it will be seenthat any load tending to deform the top flange will be resisted, notonly by the flange itself, but also by adjacent girders, thus materiallyincreasing the strength of the structure and permitting lighter girdersto be used.

With my improved construction I also equip the upturned vertical end ofthe bottom flange of each girder with an abutment so as to utilize thebottom flange for compression in the vicinity of, the supports or Ibeams 1, and avoiding any shearing or crushing action at this point.Such an abutment may be a light steel section 8 welded or otherwisesecured to the end of the bottom flange of the girder at the point wherethe bottom flange is bent upwards as shown. The girders are placed inposition and a body' of concrete 9 is cast or poured around the lowerpart of each I beam by means of usual forms or molds not shown. Theconcrete is so cast that it engages the abutment sections 8 which arethereby embedded in the concrete so as to resist compression strainsupon the bottom flanges of the girders. Each section 8 is of sufficientarea to take the thrust with out crushing the concrete in which it isembedded.

After the girders have been placed and tied together they are thencompletely embedded in a layer 1010f porous concrete or so-calledaerocrete through the use of forms or molds of usual construction, notshown. This material, when the molds are removed, forms a smooth andcontinuous ceiling for the floor below, which if desired, may e coatedwith any suitable plaster-like material. The coating 10 extends abovethe girders and constitutes the floor. It may be covered with a suitablesurfacing material.

In casting the porous concrete 10, instead of using a bottom form ofwood which re quires to be removed after the aerocrete has set, I mayuse a form comprising expanded metal lath of well known constructionsupported at a short distance belowthe bottom anges of the girders. Tosuch a metal lath when used as a form, I may apply a basic coat ofplaster on its underside before the pouring of the expanded concrete,thereby preventing the wet concrete from leaking through the lath. Afterthe expanded concrete has set I may then apply a finishing coat ofplaster to the metal lath and thus obtain a finished ceiling withouthaving to remove a wooden form and applying plaster to the undersurfaceof the expanded concrete.

The arrangement shown in Figure 2 is the same as that just described,except that instead of using light weight girders, I make use of I beams11, each having a bottom flange 12 and an upper flange 13. Such I beams,if of light weight, may be wholly embedded in a layer of porous concreteas in Figure 1, but when such I beams are of ordinary standarddimensions, it will not be necessary to use the embedding porous cementand therefore, in the latter case, I need use only a relatively thinlayer of porous concrete 14 to form the ceiling, and a similar layer 15to constitute the floor, these layers being poured by the use ofordinary forms.

When an I beam is used instead of a girder as in Figure 1, the plates 5and t are preferably bolted in place as shown. Instead of using an Ibeam 11 of suflicient strength so as not to require the use of acomplete filling of porous concrete as in Figure 1, it will beunderstood that latticed steel joists may be employed in the same way.

If desired, instead of employing ordinary concrete for covering the Ibeams 1, any of the light weight concrete may be used, such as cinderconcrete, or so-called Haydite con crete, or other concrete in whichtheaggregate is of a light, porous nature. These materials have sufiicientstrength for the purpose and have the advantage over ordinary concreteof being relativelg light.

By completely embed ing light weight girders in a mass of porousconcrete or aerocrete a very rigid construction is obtained and anytendency of the girders to buckle under the effect of load strains or ofheat in case of fire is prevented. At the same time, the arrangement isfire-proof in a very marked de ree, as well as almost entirely soundproo In my said application above identified, I refer to the possibilityof using relatively large fillers, such as bags containing a light,cheap. material, thus reducing the amount of porous concrete necessaryin forming the floor, and it will be understood that when thearrangement of Fi re 1 is used, these fillers may be employed 1fdesired.

Having now described my invention, what I claim is new therein anddesire to secure by Letters Patent is as follows:

1. In a floor construction, the combination of a series of longitudinalsupporting members, oftransverse members extending across and supportedby said members to form the s an, a bottom on each transverse member ana rigid abutment with which the bottom of each transverse member engagesto resist the effect of compression strains.

2. In a floor construction, the combination with longitudinal supportingmembers, of a series of transverse members extending crosswise betweenand carried by said longitudinal members to form the span, thetransverse members of one s an being connected rigidly to the corresponing transverse members of adjacent spans, a bottom on each transversemember and abutments with which the bottom of said transverse membersengage to resist compression strains.

3. In a floor construction, the combination with longitudinal supportingmembers, of a series of light weight irders extending crosswise betweenand earned by said longitudinal members to form the span, the girders ofone span being connected rigidly to the corres nding girders of adjacentspans, bottom anges on said girders, abutments with which the bottomflanges of said girders en age and a filling of porous concrete in whicall the girdersare embedded.

4. In a floor construction the combination of a series of longitudinalmembers, a body of concrete surrounding each member, abutments embeddedin said concrete, light weight cross girders extending between the lonitudinal members and supported thereby to orm a span, said girdershaving bottom flanges which engage with said abutments to resistcompression strains, and a filling of porous concrete in which saidgirders are embedded. u

5; In a floor construction, the combination with a series oflongitudinal members and a body of concrete surrounding each of said,

members, of a plurality of transverse members extending crosswise andsupported thereb to form a span, the transverse members 0 one span beingconnected to the corresponding transverse members of an adjacent span,and the transverse members having bottom flanges which are engaged withthe adjacent concrete covering the longitudinal members to resistcompression strains.

6. In a floor construction, the combination with a series oflongitudinal members and a body of concrete surrounding each of saidmembers, of a plurality of light weight girders extending crosswise andsupported thereby to form a s an, the girders of one s an being connecteto the corresponding gir ers of an adjacent span, the. compressionmembers of all the girders being in enga ement with the adjacentconcrete covering t e longitudinal members to resist compressionstrains, and a filling of porous concrete in "which all the girders areembedded.

KARL P. BHJLNER-

